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Comment by codex | Hacker News Reader

I didn't know this before, but SpaceX has only done eight launches so far--half of them test flights. Perhaps this explains the anomaly.

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I doubt that. If a software startup designed and built a distributed system that would automatically detect and recover from hardware faults (see: every 'design for failure' post ever), would you say that the hardware faults were due to inexperience or incompetence? Building redundancy into the system was a conscious decision, and they weren't "lucky" to have flown through this anomaly.

You misundersand me. Failures are not due to inexperience. High failure rates are. If a single failure occurs in one out of eight launches, a double will occur once every sixty four. While I believe the Falcon is double fault tolerant, I don't believe for a minute that this is the first failure seen in a SpaceX launch. If they've seen only one other failure in their eight launches, their overall failure rate (resulting in loss of rocket, possibly cargo and crew) would be one in 64. That is nearly the failure rate of the Shuttle. With more experience, they may be able to lengthen their mean time to loss (MTTL) by improving the failure rate.

First of all, this launch was not a failure, full stop.

I don't know what your background in statistics is, but I'm impressed that you're able to deduce the details of a such a complicated, stochastic process, from only 8 observations, and are willing to extrapolate your predictions for 8 times as many more.

And for someone who loves to comment negatively on SpaceX/Tesla posts, maybe you could spend 5 minutes looking at their Wikipedia pages and see that yes, there have been failures (i.e. unable to achieve stated mission goals and sometimes destroying payloads).

The mission wasn't a failure, but a major component failed in a way that is very concerning. There is a lot of work to be done before a sane human being will get in one of those, let alone approach the safety record of aircraft that Musk is so fond of alluding to.

If you feel that you are qualified to say it is a very concerning component failure based on the scant evidence available, then that's up to you.

I am, and of course it is concerning - the engine shut down and debris was strewn about. Do the math on the failure rates. Unless things are dramatically improved (the goal of course), these things are just not safe for people outside of the dare-devil set. That's not a knock against Space X - this is hard stuff. It is a slight knock against Musk's over-the-top marketing that has us on Mars in 15 years, which, in my opinion, is unrealistic.

This was basically equivalent to a hard disk failing inside a RAID array. Though I think hard disk failures are more common than engine failures.

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